Bearing isolating seal

ABSTRACT

A bearing-isolating seal ( 40 ) comprises a metal seal member ( 50 ) and a non-metal seal member ( 60 ). The seal members ( 50, 60 ) comprise radial walls ( 51 - 53, 61 - 62 ) defining annular slots ( 55 - 56, 65 ) that together form a labyrinth-like path through the seal ( 40 ). The spindle-side wall ( 62 ) of the metal seal member ( 50 ) is sized for press-fit attachment around a spindle and the roller-side wall ( 51 ) of the non-metal seal member ( 60 ) is adapted to receive a roller therearound.

A belt conveyor, such as that used in the mining industry, typicallyemploys a series of stands or pedestals on which idler rollers arerotatably mounted to fixed shafts. The rollers usually each include abearing mounted within a chamber within the roller hub. A seal can beprovided to seal the annular space between the roller hub and thespindle to prevent leakage of lubricant from the bearing chamber andprevent the ingress of contaminants thereinto.

SUMMARY

A seal is provided for sealing the annular space between a roller huband a spindle to prevent lubricant leakage and/or contaminant ingress.The seal comprises a metal seal member and a non-metal (e.g., plastic)seal member that, without contacting, together form a labyrinthlike-path. The seal members can be made from lower-cost materials and/ormade by less-expensive manufacturing methods than traditional labyrinthseals. For example, the metal seal member can be made from a non-bronzemetal and it can be made by a non-machining method such as molding orstamping. The non-metal seal member can be made from a non-PTFE materialand likewise made by a non-machining method.

DRAWINGS

FIG. 1 is a front view of three idler rollers mounted on a stand.

FIG. 2 is a sectional view of a roller, its spindle, its bearing, andits seal.

FIG. 3 is a sectional view of the seal.

DESCRIPTION

Referring now to the drawings, and initially to FIG. 1, three idlerrollers 10 are shown mounted in a wing-like configuration with the outerrollers being angled upwardly oriented and the center roller 10 beinggenerally horizontal. The rollers 10 can be adapted to, for example,support conveyor belts. In any event, the rollers 10 are mounted forrotation relative to spindles 20 which are in turn attached to supportmembers of a stand or other pedestal.

A roller 10, its spindle 20, and other interfacing components are shownin more detail in FIG. 2. These interfacing components can include abearing 30 mounted within a bearing chamber 11 in the hub 12 of theroller 10. The bearing 30 can comprise an outer race 31 attached to theroller hub 12 and an inner race 32 attached to the spindle 12 in aconventional manner. A seal 40 is provided to seal the annular spacebetween the roller hub 12 and the spindle 20 to prevent leakage of thelubricant from the bearing chamber 11 and to prevent ingress ofcontaminants thereinto.

The seal 40 is shown isolated from the roller 10, the spindle 20, andthe bearing 30 in FIG. 3. The seal 40 comprises a metal sealing member50 and a plastic sealing member 60. The orientation of the seal 40and/or the members 50/60 can be explained by reference to theroller-side (nearest the roller 10), the spindle-side (adjacent thespindle 20), the bearing-side (closest to the bearing 30), and theair-side (outside the confines of the roller 10).

The metal seal member 50 comprises three radial walls 51-53 and an axialwall 54 from which they perpendicularly project in the bearing-sidedirection. A roller-side slot 55 is formed between the radials wall 51and 53, and a spindle-side slot 56 is formed between the radial walls 52and 53. The roller-side surface of the radial wall 52 has a notch 57near its bearing-side end.

The walls 51-54 have substantially the same and/or a constant thickness,except for intermediate wall 53 which tapers radially outward in theair-side direction. The spindle-side radial wall 52 is the longest inthe axial dimension, with the intermediate radial wall 53 being slightlyshorter, and the roller-side radial wall 51 being substantially shorterthan the walls 52-53. The spindle-side radial wall 52 is radially sizedto be press-fit around the spindle 20 and remain non-rotatably fixedthereto during relative rotation of the roller 10.

The non-metal seal member 60 comprises radial walls 61-62 and an axialwall 64 from which the perpendicularly project in the air-sidedirection. The radial walls 61 and 62 extend approximately the sameaxial length and they form a slot 65 therebetween. The axial wall 61 isradially sized for receipt of the roller 10 (and/or its hub 12)therearound and remains non-rotatably fixed thereto during relativerotation of the roller 10.

The roller-side radial wall 61 has a triangular shape tapering radiallyinward in the bearing-side direction. The spindle-side axial wall 62 andthe axial wall 64 have substantially the same and/or a constantthickness. A stepped flange 66 extends radially outward from theair-side end of the roller-side wall 61. A ramped tab 67 extendsradially inward from the spindle-side end of the axial wall 64, and arounded-corner projection 68 extends axially inward from this wall'sroller-side end.

The intermediate radial wall 53 of the metal seal member 50 is situatedwithin the slot 65 in the non-metal seal member 60. The stepped flange66 of the non-metal seal member 60 is situated within the roller-sideslot 56 of the metal seal member 50. And the ramped tab 67 of thenon-metal seal member 60 is situated within the notch 57 of thespindle-side leg 52 of the metal member 50. This intertwined-likesituating of the seal members 50 and 60 forms a labyrinth path throughthe seal member 40.

The shortness of the roller-side radial wall 51 of the metal seal member50 and/or the stepped geometry of the flange 66 of the non-metal sealmember 50 can facilitate installation of the seal 40. Specifically, theshort metal wall 51 can be deflected inwardly against the flange 66 asthe seal 40 is pushed into roller 10. When the seal 40 reaches theproper position, and the installation tool is removed, the wall 51and/or flange 66 will recoil creating a clearance therebetween.

The rounded projection 68 of the non-metal seal member 60 may be helpfulin diverting contaminant flow in an unusually severe application.

The metal seal member 50 can be made of any suitable metal (e.g.,bronze, aluminum, stainless steel, tin, etc.) by any suitable technique(e.g., machining, stamping, molding, etc.). The non-metal seal member 60can be made of any suitable plastic material (e.g.,polytetrafluoroethylene, fluoroelastomers, rubber, nylon, etc.) by anysuitable technique (e.g., machining, molding, injection molding, etc.).That being said, an advantage of the seal 40 is that it can be made withlower-cost materials and methods than those conventionally used forlabyrinth-like seals. Specifically, for example, the metal member 50 canbe made from non-bronze metal by a non-machining method (e.g., stamping,molding), and/or the non-metal member 60 can be made from a non-PTFEplastic by a non-machining method (e.g., molding, injection molding).

Although the roller 10, the seal 40, and/or the seal members 50 and 60,have been shown and described with respect to a certain embodiments,equivalent alterations and modifications should occur to others skilledin the art upon review of this specification and drawings. If an element(e.g., component, assembly, system, device, composition, method,process, step, means, etc.), has been described as performing aparticular function or functions, this element corresponds to anyfunctional equivalent (i.e., any element performing the same orequivalent function) thereof, regardless of whether it is structurallyequivalent thereto. And while a particular feature may have beendescribed with respect to less than all of embodiments, such feature canbe combined with one or more other features of the other embodiments.

1. A bearing-isolating seal (40) for installation on a roller (10) that rotates relative to a spindle (20) and has a bearing (30) interposed therebetween; wherein the seal (40) comprises a metal seal member (50) and a non-metal seal member (60); wherein the metal seal member (50) comprises: a roller-side radial wall (51), a spindle-side radial wall (52) sized for attachment to the spindle (20), an intermediate wall (53) located radially between the roller-side wall (51) and the spindle-side wall (52), an axial wall (54) from which the radial walls (51, 52, 53) perpendicularly project in the bearing-side direction, a roller-side slot (55) between the roller-side wall (51) and the intermediate wall (53), and a spindle-side slot (56) between the spindle-side wall (52) and the intermediate wall (53); wherein the non-metal seal member (60) comprises: a roller-side radial wall (61) for attachment to the roller (10), a spindle-side radial wall (62), an axial wall (64) from which the spindle-side wall (61) and the roller-side wall (62) perpendicularly project in the air-side direction, and a slot (65) between the roller-side radial wall (61) and the spindle-side radial wall (62); and wherein the intermediate radial wall (53) of the metal seal member (50) is situated within the slot (65) of the non-metal seal member (60), and the spindle-side radial wall (62) of the non-metal seal member (60) is situated within the spindle-side slot (56) of the metal seal member (50).
 2. A seal (40) as set forth in the preceding claim, wherein the spindle-side wall (52) of the metal seal member (50) has a notch (57) on its roller-side surface of the spindle-side wall (52); wherein the axial wall (64) of the non-metal seal member (60) has a tab (67) extending radially inward from its spindle-side end; and wherein the tab (67) is situated within the notch (57).
 3. A seal (40) as set forth in the preceding claim, wherein the tab (67) has a ramped edge that ramps radially inwardly in the bearing-side direction.
 4. A seal (40) as set forth in any of the preceding claims, wherein the roller-side wall (61) of the non-metal seal member (60) has a flange (66) extending radially outward from its air-side end of the roller-side wall (61); and wherein the flange (66) is situated within the roller-side slot (55) of the metal seal member (50).
 5. A seal (40) as set forth in the preceding claim, wherein the flange (66) has a stepped profile.
 6. A seal (40) as set forth in any of the preceding claims, wherein the axial wall (64) of the non-metal seal assembly has a projection (68) extending axially, in the bearing-side direction, from its roller-side end.
 7. A seal (40) as set forth in the preceding claim, wherein the projection (68) has rounded corners.
 8. A seal (40) as set forth in any of the preceding claims, wherein the walls (51, 52, 53, 54) of the metal seal member (50) have substantially the same and/or a constant thickness, except for the radial intermediate wall (53) which tapers radially outward in the airside direction.
 9. A seal (40) as set forth in any of the preceding claims, wherein the radial walls (51, 52, 53) of the metal seal member (50) have different axial dimensions, with the spindle-side radial wall (52) being the longest, the intermediate radial wall (53) being slightly shorter, and the roller-side radial wall (51) being substantially shorter than the other radial walls (52, 53).
 10. A seal (40) as set forth in any of claims 1-9, wherein the metal seal member (50) is made from bronze.
 11. A seal (40) as set forth in any of claims 1-9, wherein the metal seal member (50) is made from a non-bronze metal.
 12. A seal (40) as set forth in the preceding claim, wherein the metal seal member (50) is made from aluminum, stainless steel, and/or tin.
 13. A seal (40) as set forth in any of the preceding claims, wherein the metal seal member (50) is made by a non-machining method.
 14. A seal (40) as set forth in the preceding claim, wherein the metal seal member (50) is made by stamping or molding.
 15. A seal (40) as set forth in any of the preceding claims, wherein the non-metal seal member (60) is made of a plastic material.
 16. A seal (40) as set forth in the preceding claim, wherein the plastic seal member (60) is made from a non-PTFE plastic.
 17. A seal (40) as set forth in the preceding claim, wherein the seal member (60) is made of rubber or nylon.
 18. A seal (40) as set forth in any of the preceding claims, wherein the non-metal seal member (60) is made by a non-machining method.
 19. A seal (40) as set forth in the preceding claim, wherein the non-metal seal member (60) is made by a molding method.
 20. A seal (40) as set forth in the preceding claim, wherein the non-metal seal member (60) is made by an injection molding method.
 21. A roller (10), a spindle (20), a bearing (30) interposed between the roller (10) and the spindle (20) in a bearing chamber (11), and a seal (40) as set forth in any of claims 1-20 sealing an annular space between the roller (10) and the spindle (20).
 22. A roller (10), a spindle (20), a bearing (30), and a seal (40) as set forth in the preceding claim, wherein the bearing (30) comprises an inner race (31) attached to the spindle (20) and an outer race (32) attached to the roller (10). 